A fine map of Sicily, on the unusually large scale of 1 in 50,000, or 1·266 inch to a mile, was constructed by the Stato Maggiore of the Italian government, between 1864 and 1868. The portion relating to Etna, and its immediate surroundings occupies four sheets. All the small roads and rivulets are introduced; the minor cones and monticules are placed in their proper positions, and the elevation of the ground is given at short intervals of space over the entire map. An examination of this map shows us that distances, areas, and heights, have been repeatedly misstated, the minor cones misplaced, and the trend of the coast line misrepresented. For example, if we draw a line due north and south through Catania, and a second line from the Capo di Taormina, (the north-eastern limit of the base of Etna), until it meets the first line at Catania, the lines, will be found to enclose an angle of 26°. If we adopt the same plan with Gemellaro's map, the included angle is found to be 53°, and in the case of the maps of Ferrara and Recupero more than 60°. Again, it has been stated on good authority, that the lava of 396 B.C. which enters the sea at Capo di Schiso flowed for a distance of nearly 30 miles; the map shows us that its true course was less than 16 miles. Lyell in 1858 gives a section of the mountain from West 20° N., to East 20° S., but a comparison with the new map proves that the section is really taken from West 35° N. to East 35° S., an error which at a radius of ten miles from the crater would amount to a difference of nearly three miles. The mantle of Carlo Gemellaro appears to have fallen upon Cav. Orazio Silvestri, Professor of Chemistry in the University of Catania. He has devoted himself with unwearying vigour to the study of the mountain, and his memoirs have done much to elucidate its past and present history. His most recent work of importance on the subject is entitled _I Fenomeni Vulcanici presentati dall'Etna nel 1863-64-65-66_. It was published in Catania in 1867, and contains an account of some very elaborate chemico-geological researches. CHAPTER II. PHYSICAL FEATURES OF THE MOUNTAIN. Height.--Radius of Vision from the summit.--Boundaries.--Area.-- Population.--General aspect of Etna.--The Val del Bove.--Minor Cones.--Caverns.--Position and extent of the three Regions.--Regione Coltivata.--Regione Selvosa.--Regione Deserta.--Botanical Regions.-- Divisions of Rafinesque-Schmaltz, and of Presl.--Animal life in the upper Regions. In the preceding chapter we have discussed the history of Mount Etna; the references to its phenomena afforded by writers of various periods; and the present state of the literature of the subject. We have now to consider the general aspect and physical features of the mountain, together with the divisions of its surface into distinct regions.